Evaporator



Mink 11 1 924.

C. D. LEBERMUTH EVAPORATOR Filed Jan. 17 1920 3 Sheets-Sheet 1 N\\ J 151 ,41 i i :1 Er. N In... \N 1 $1:

March 11 1924.

' 1,486,387 c. D. LEBERMUTH EVAPORATOR Filed Jan. 17, 1920 3 Sheets-Sheet 2 March 11 1924. 1,486,387

C.D.LEBERMUTH EVAPCRATOR Filed Jan. 17. 1920 I s Sheets-Sheet 5 Patented Mar. H, 1924.

CLARK I). LEBERMU'II-I, OF DONALDSO'NVILLE, LOUISIANA.-

EVAPORATOR.

Application filed January 17, 1920.

To all whom it may concern.

Be it known that I, CLARK D. LEBER- MUTII, a citizen of the United States, and a resident of Donaldsonville, in-the parish of St. James and State of Louisiana, have invented certain new and useful Improvements in Evaporators, of which the follow ing is a specification.

My invention relates to evaporators for treating liquors such as cane syrup and-various products for the purpose of evaporating part of the liquid content to increase the density of the body of material. In evaporators of the class to which the present one belongs it has been common practice to -provide upper and lower tube sheetswith aseries of small tubes between the sheetsfor the upward flow of the liquor and a series of larger tubes for the down How thereof, with a steam belt around these tubesand a vapor chamber or dome above the tubes. In the previous systems there-has been a tank or receptacle containing a single-body of liquor. Also, there has been no defined path or system of liquor circulation, except that the liquor flowed up through the smaller tubes and returned through the larger ones to the same body in the tank. The difliculty with such systems has been that the average density of liquor in contact with the heating surface has been nearly equal to the final density and the coefficient of heat transmission has therefore been low.

The object of my, invention is to providea more economical evaporator. In the same unit I subject the liquor to the action of a heating medium of one temperature, that is, I transmit heat thereto in a single vapor or steam phase, and I provide a defined circulation for the liquorunder treatment. In the full embodiment of my invention the liquor is caused to fiow through several paths, passing progressively from one compartment to another, each successive compartment containing more dense liquor. The average density of evaporated liquor in contact with the heating surface is muchless than the average density in contact with the heating surface in former devices, and therefore the coefficient-of heat transmission in the present case-is much greater and the apparatus is more eflicient in operation. So far as I am aware, thisis the first Serial No. 352,113.

instance where the liquor has been compelled to circulate in more than one defined path or where the evaporated liquor has been compelled to travel progressively from one compartment or body of liquor to another greater density so that the average sion of heat to the liquor.

In the present apparatus I overcomethis defect or lack of efiiciency.

In the present case I have shown a single unit or evaporator but it will be understood that others may be added thereto to provide multiple effects and the method of associat ing the evaporators will be understood by those skilled in the art, sothat while I have shown but one unit it is to be understood that the present device is adapted for use in multiple effects and that the same efliciency will obtain throughout the system.

In the drawings forming part of this application,

Figure 1 is a vertical sectional view of my improved apparatus, in which I have shown only a portion of the vapor chamber since the latter may conform to present practice,

Figure 2 is a horizontal sectional view showing the upper tubesheet and the tubes,

and

Figure 3 is a horizontal sectional view taken just above the lower tube sheet, showing the latter and the tubes.

Figure 4; is a horizontal sectional view showing in detail thewarrangement of bafiieplate and upwardly projectingdown-take tubes.

The invention is shown herein in desirable form but it is to be-understood that the same is subject to various modifications without departlng from the broad features 105 of novelty.

' a metal body of circular form and constructed of an upper section 2, a middle section 3 and the arched bottom section 4, these being secured together by liquid tight joints in any desired manner. The upper section 2 forms a vapor chamber 5 above the tube sheets and into which the vapors caused by evaporation of the liquor rise and from which they pass into another evaporator, Where a multiple effect is used, or the vapors are disposed of in any other well known way. The bottom section 4 forms the liquor tank wherein a quantity or supply of liquor is maintained, generally at a definite level which is sufficient to maintain'liquor in the lower ends of the tubes. The tank 4 is preferably, though not necessarily, circular and it is divided into a plurality of separate compartments which are preferably of annular shape, the compartments being concentrically arranged in relation to each other. The means for dividing the tank into compartments need not form a perfect liquid tight separation of the compartments but they should be such as will prevent a general and-direct circulation of the liquor from one compartment to another. I have shown a plate or wall 6 of circular form resting on the bottom of the shell section 4 inside the angle metal ring 7, and extending upwardly to or nearly to the bottom tube sheet 8. This wall 6 is preferably concentric relatively to the side wall of the section 4 so that an annular compartment 9 is formed between the dividing wall 6 and the tank wall into which coinpartment the liquor to be treated is originally introduced. The thin liquor is introduced into this compartment through the pipe 10 which extends partly around the compartment and is provided with a number of small apertures 11 through which the liquor discharges.

I have arranged a second wall 12 inside the tank 4 and this is preferably circular and arranged concentrically of the wall 6 and it is spaced from the latter to form a second compartment 13 in the tank, of annular shape.

There is shown a third wall 14 concentrically disposed in relation to the wall 12 and this forms a compartment 15 of annular shape and its interior provides a liquor chamber 16 to which the pipe 17 for discharging the thick or treated liquor is connected.

The bottom tube sheet 8 extends across the apparatus at the top of the tank 4 and some distance above the bottom tube sheet 1 pro vide a top tube sheet 18. Between these tube sheets and within the section 3 there is a closed heating, vapor or steam chamber 19 into which hot vapor or steam flows from any suitable source, as in present practice. I have shown no balfles for the hot vapors in the chamber or belt 19 but it will be underrecess? stood that any form of baflles may be used therein for causing the heating vapors to follow a defined path of circulation.

There are pipes 21 leading from the bottom tube sheet 8 through and below the tank 4 and these connect with a common discharge pipe 22 for conducting the liquid condensation from the chamber 19 to any suitable condensing pump or discharge. There is a pipe 17 connected with the bottom of the central chamber 16 within the wall 14 and the concentrated thick or treated liquor is discharged through this pipe. There are pipes 20 extending through the tube sheets and leading through the wall of the section 2 where they are provided with valves 23 and they connect with a common discharge pipe 24 and these various pipes are for the purpose of discharging or leading off the non-condensible (ammonia) gases from the bottom compartments and they conform to present practice in the art.

There are upfiow and downflow tubes connected between the tube sheets 8, 18 and in which the principal evaporation action takes place; and in addition, there are devices or baiiles for causing a definite movement or circulation of the liquor. Above the liquor compartment 9 and substantially coextensive with the Whole area thereof there are smaller tubes 25 having a liquid tight connection with the tube sheet 8 at their lower ends and with the top tube sheet 18 at their upper ends. I prefer to arrange these tubes in such form as will permit the greatest number in the space provided for them and I have indicated one plan of arrangement for these tubes. It will be understood that in Figures 2 and 3 T have indicated only part of these tubes and that there are as many as the space will permit. These smaller tubes 25 are the upflow tubes wherein the liquor or vapor or both, rise from the tank compartment 9 to the top of the tube sheet 18 and they are heated by the hot vapor or steam in the heating belt or compartment 19. As the thin liquor is introduced into the compartment 9 in the first instance the liquor first circulates through the tubes 25 to the space above the top tube sheet 18. There are tubes 26 of larger diameter than the upflow tubes 25 and these are arranged prefer- .ably concentrically of the tubes 25. There is a baflie plate 27 rising up from the upper tube sheet 18 and it forms a baflle line betweenthe various tubes 26 as shown in Figure 2 and the tops of the tubes 26 are cut away on one side 28, as shown, so that they lie substantially flush with the top tube sheet, whereas, a portion 29 of the tube rises some distance above the tube sheet 18 and the baffle plate 27 passes around the rear surface of these projections 29 and it is secured thereto. It will be observed that the liquor which rises in the tubes 25 from the first compartment-Q-givesoffi some of its vaporwhich rises in the vapor'space '5, and the liquor passes downwardly through the several tubes 26. As the liquor spreads over the tube sheet 18 the baflle plate 27 prevents it from spreadingbeyond this first series of tubes audit. is compelled to flow downwardly through the tubes 26, that is, its course of circulation is definitely controlled.

It will be noted that the downfiow tubes 26 which receive the liquor from the tubes discharge at their lower ends into the liquor compartment 13 which is separated from the compartment 9, except that the liquor may flow from one to the other in the defined path as described. Within the series of tubes 25, 26 there is another series of small upfiow tubes which at their lower ends open into the second compartment 13 and at their upper ends terminate near the top tube sheet 18 to the inside of the bafile plate 27. The liquor rising in the tubes 25 and 30 can not commingle at the top of the tube sheet because of the bafile plate 27. The liquor rising in the tubes 30 gives off some of its vapor into the vapor space 5 and this liquor flows downwardly through another series of downfiow tubes 31. There is a second bafiie plate 32 connected with the inner, projecting sides 33 of the tubes 31, so that the liquor rising in the tubes 30 must flow downwardly through the tubes 31 as both bafiies 27 and 32 define or limit its circulation and compel it to follow this course. The lower ends of the downfiow tubes 31 terminate inside the wall 12 so that they discharge into the compartment 15, which is separate from the compartments 13 and 9. I have shown another series of upfiow tubes 34; through which the liquor from the compartment15 may flow to the top of the upper tube sheet 18 and these terminate within the bafiie plate 32. The liquor which rises in the tubes 34: is compelled to flow d0wnwardly through the large central tube from which it discharges through the outlet pipe 17 The arrangement above described compels the liquor to circulate in defined paths. It first enters the compartment 9 as a thick liquor, it rises due to the transmission of heat, in the tubes 25 to the top tube sheet 18; thence it flows downwardly in the larger tubes 26 to the compartment 13. As the liquor by this time has given off some of its vapor the liquor in the compartment 13 will naturally be more dense or concentrated than the liquor in the compartment 9. From the compartment 13 the liquor rises in the tubes 30, gives off more vapor and then flows downwardly in the tubes 31 to the compartment 15. In the latter the liquor will be more dense than in either the compartments 13 or 9. From the compartment 15 the liquor rises in the tubes 34:, gives ofi more of its vapor, and flows into the tube or well 35 wherein the liquor is at the maximum density reached in the apparatus. All the tubes are heated by the vapor or steam in the'common compartment 19 so that the liquor is all treated in the same steam phase.

It will be apparent that by causing the liquor to travel a defined course of circulation and by causing it to pass progressively into separate bodies or compartments where the densities are successively higher than the average density of all the liquor in contact with the heating surfaces is less than in former apparatus and the coefficient of heat transmission is therefore greater, whereas, in former devices the average density of liquor in contact with the heating surfaces is nearly equal to the final or maximum density.

I prefer the concentric arrangement shown herein because it provides for a lesser number of tubes 30 than there are tubes 25, and for a lesser number of tubes 34 than there are tubes 30 so that there is a gradual decrease in the area of the heating surface as the liquor increases in density and decreases in quantity and while it is travelling in its defined course of circulation.

Modifications may be made in the construction without departing from the scope of my invention and I therefore desire to include all forms coming within the scope of the annexed claims.

Having described my invention, what I claim is:

1. An evaporator comprising means for holding separate bodies of liquor under treatment, upper and lower tube sheets, tubes for each of said holding means arranged between said tube sheets and in which the liquor from said holding means is adapted to rise to the upper tube sheet, the tubes from one of said holding means being disposed concentrically relatively to those from an adjacent holding means, tubes larger than said first mentioned tubes between said tube sheets, adapted to receive the liquor which rises from one of said holding means and to return it to another of said holding means whereby the liquor circulates progressively from one of said holding means to another, and means for heating said tubes in the same vapor or steam phase.

2. An evaporator comprising a tank and means for dividing it into a plurality of concentric compartments for holding separate bodies of liquor under treatment, spaced tube sheets above said tank, a plurality of upfiow tubes in said tube sheets, communi eating at their lower ends with the several compartments in said tank, a plurality of downfiow tubes larger than said upfiow tubes in said tube sheets adapted to receive the liquor which rises in said smaller tubes and to return it to said several compartments in said tank, baffle plates extendin upwardly from said top tube sheet an adapted to cause the liquor which rises in the smaller tubes from one compartment to sively from one compartment toanother, and means for heating all ofsaid tubes in the same vapor or steam phase. r

Signed at New York, in the county of New York and State of New York, this 19th day of September, 1919.

CLARK D. LEBERMUTH. 

